准备知识点:
1.邮件授权码
2.telnet服务开启
3.base64编码
4.smtp协议简单使用
5.windows socket编程
详细流程:
1.邮件授权码在:设置-pop3/SMTP/IMAP里设置
2.telnet服务开启:控制面板-程序-启动或关闭windows功能-telnet客户端
3.base64编码
Base64是网络上最常见的用于传输8Bit字节码的编码方式之一
第一步,将待转换的字符串每三个字节分为一组,每个字节占8bit,那么共有24个二进制位。
第二步,将上面的24个二进制位每6个一组,共分为4组。
第三步,在每组前面添加两个0,每组由6个变为8个二进制位,总共32个二进制位,即四个字节。
第四步,根据Base64编码对照表(见下图)获得对应的值
--最终将要传输的字符都变成可见字符,这样防止经过网络上一些只支持可见字符的计算机而出问题,这边的加密和解密方式时固定的,因此对安全性没有啥特别好的保护
4.smtp协议简单使用 --注意账号和密码都要经常base64加密,并且密码是授权码
在cmd窗口里:
telnet
open smtp.163.com 25
即会进入以下界面,并进行图片里操作即会发出邮件:
密码被涂掉了,请谅解,ZWZmb3J0c2NvZGVwYW5kYQ== 即是 efforscodepanda的base64加密而来
发往163自己是因为第三方不携带自身的邮箱地址会报554操作,而且发给自己的邮箱也能查的到
5.windows socket编程 --具体注意点很多,基础知识部分请大家自己学习
这边特别感谢:https://blog.csdn.net/sinat_36219858/article/details/80439782
源码:
#include <iostream> #include <string> #include <vector> #include <fstream> #include <WinSock2.h> //适用平台 Windows #pragma comment(lib, "ws2_32.lib") /*链接ws2_32.lib动态链接库*/ // POP3服务器(端口:110) Csmtp服务器(端口:25) using namespace std; class Csmtp { int port; string domain; string user; string pass; string target; string title; //邮件标题 string content; //邮件内容 HOSTENT* pHostent; SOCKET sockClient; //客户端的套接字 vector <string> filename; //存储附件名的向量 public: Csmtp( int _port, //端口25 string _domain, //域名 string _user, //发送者的邮箱 string _pass, //密码 string _target) //目标邮箱 :port(_port), domain(_domain), user(_user), pass(_pass), target(_target){};//内容 bool CReateSocket(); void setTitle(string tem){ title = tem; } void setContent(string tem){ content = tem; } int SendAttachment(SOCKET &sockClient); int SendMail(); void addfile(string str){ filename.push_back(str); } };
#include "Csmtp.h" //#include <afx.h>//异常类 static const char base64Char[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; char* base64Encode(char const* origSigned, unsigned origLength) { unsigned char const* orig = (unsigned char const*)origSigned; // in case any input bytes have the MSB set if (orig == NULL) return NULL; unsigned const numOrig24BitValues = origLength / 3; bool havePadding = origLength > numOrig24BitValues * 3; bool havePadding2 = origLength == numOrig24BitValues * 3 + 2; unsigned const numResultBytes = 4 * (numOrig24BitValues + havePadding); char* result = new char[numResultBytes + 3]; // allow for trailing '/0' // Map each full group of 3 input bytes into 4 output base-64 characters: unsigned i; for (i = 0; i < numOrig24BitValues; ++i) { result[4 * i + 0] = base64Char[(orig[3 * i] >> 2) & 0x3F]; result[4 * i + 1] = base64Char[(((orig[3 * i] & 0x3) << 4) | (orig[3 * i + 1] >> 4)) & 0x3F]; result[4 * i + 2] = base64Char[((orig[3 * i + 1] << 2) | (orig[3 * i + 2] >> 6)) & 0x3F]; result[4 * i + 3] = base64Char[orig[3 * i + 2] & 0x3F]; } // Now, take padding into account. (Note: i == numOrig24BitValues) if (havePadding) { result[4 * i + 0] = base64Char[(orig[3 * i] >> 2) & 0x3F]; if (havePadding2) { result[4 * i + 1] = base64Char[(((orig[3 * i] & 0x3) << 4) | (orig[3 * i + 1] >> 4)) & 0x3F]; result[4 * i + 2] = base64Char[(orig[3 * i + 1] << 2) & 0x3F]; } else { result[4 * i + 1] = base64Char[((orig[3 * i] & 0x3) << 4) & 0x3F]; result[4 * i + 2] = '='; } result[4 * i + 3] = '='; } result[numResultBytes] = '\0'; return result; } int Csmtp::SendAttachment(SOCKET &sockClient) /*发送附件*/ { for (std::vector<string>::iterator iter = filename.begin(); iter != filename.end(); iter++) { cout << "Attachment is sending··· " << endl; string path = *iter; ifstream ifs(path, ios::in | ios::binary); //'或链接2个属性,以输入、二进制打开' if (false == ifs.is_open()) { cout << "无法打开文件!" << endl; return 1; } string sendstring; sendstring = "--@boundary@\r\nContent-Type: application/octet-stream; name=\"1.jpg\"\r\n"; sendstring += "Content-Disposition: attachment; filename=\"1.jpg\"\r\n"; sendstring += "Content-Transfer-Encoding: base64\r\n\r\n"; send(sockClient, sendstring.c_str(), sendstring.length(), 0); //infile.read((char*)buffer,sizeof(数据类型)); // get length of file: ifs.seekg(0, ifs.end); int length = ifs.tellg(); ifs.seekg(0, ifs.beg); cout << "length:" << length << endl; // allocate memory: char * buffer = new char[length]; // read data as a block: ifs.read(buffer, length); ifs.close(); char *pbase; pbase = base64Encode(buffer, length); delete[]buffer; string str(pbase); delete[]pbase; str += "\r\n"; int err = send(sockClient, str.c_str(), strlen(str.c_str()), 0); if (err != strlen(str.c_str())) { cout << "附件发送出错!" << endl; return 1; } } return 0; } bool Csmtp::CReateSocket() { WSADATA wsaData; WORD wVersionRequested = MAKEWORD(2, 1); //WSAStarup,即WSA(Windows SocKNDs Asynchronous,Windows套接字异步)的启动命令 int err = WSAStartup(wVersionRequested, &wsaData); cout << "WSAStartup(0:successful):" << err << endl; char namebuf[128]; //获得本地计算机名 string ip_list; if (0 == gethostname(namebuf, 128)) { struct hostent* pHost; //获得本地IP地址 pHost = gethostbyname(namebuf); //pHost返回的是指向主机的列表 for (int i = 0; pHost != NULL&&pHost->h_addr_list[i] != NULL; i++) { string tem = inet_ntoa(*(struct in_addr *)pHost->h_addr_list[i]); ip_list += tem; ip_list += "\n"; } } else { cout << "获取主机信息失败..." << endl; } ////////////////////////////////////////////////////////////////////////// title = namebuf;// 邮件标题 content = ip_list; //主机ip sockClient = socket(AF_INET, SOCK_STREAM, 0); //建立socket对象 pHostent = gethostbyname(domain.c_str()); //得到有关于域名的信息 if (pHostent == NULL) { printf("创建连接失败,也许没联网!\n"); return false; } return true; } int Csmtp::SendMail() { char *ecode; char buff[500]; //recv函数返回的结果 int err = 0; string message; // SOCKADDR_IN addrServer; //服务端地址 addrServer.sin_addr.S_un.S_addr = *((DWORD *)pHostent->h_addr_list[0]); //得到smtp服务器的网络字节序的ip地址 addrServer.sin_family = AF_INET; addrServer.sin_port = htons(port); //连接端口25 //int connect (SOCKET s , const struct sockaddr FAR *name , int namelen ); err = connect(sockClient, (SOCKADDR*)&addrServer, sizeof(SOCKADDR)); //向服务器发送请求 cout << "connect:" << err << endl; //telnet smtp.126.com 25 连接服务器结束 buff[recv(sockClient, buff, 500, 0)] = '\0'; cout<<"connect:"<<buff<<endl; message = "ehlo 126.com\r\n"; send(sockClient, message.c_str(), message.length(), 0); buff[recv(sockClient, buff, 500, 0)] = '\0'; cout<<"helo:"<<buff<<endl; message = "auth login \r\n"; send(sockClient, message.c_str(), message.length(), 0); buff[recv(sockClient, buff, 500, 0)] = '\0'; cout<<"auth login:"<<buff<<endl; //上传邮箱名 message = user; ecode = base64Encode(message.c_str(), strlen(message.c_str())); message = ecode; message += "\r\n"; delete[]ecode; send(sockClient, message.c_str(), message.length(), 0); buff[recv(sockClient, buff, 500, 0)] = '\0'; cout<<"usrname:"<<buff<<endl; //上传邮箱密码 message = pass; ecode = base64Encode(message.c_str(), strlen(message.c_str())); message = ecode; delete[]ecode; message += "\r\n"; send(sockClient, message.c_str(), message.length(), 0); buff[recv(sockClient, buff, 500, 0)] = '\0'; cout<<"password:"<<buff<<endl; message = "mail from:<" + user + ">\r\nrcpt to:<" + target + ">\r\n"; send(sockClient, message.c_str(), message.length(), 0); buff[recv(sockClient, buff, 500, 0)] = '\0'; cout<<"mail from: "<<buff<<endl; buff[recv(sockClient, buff, 500, 0)] = '\0'; cout<<"rcpt to: "<<buff<<endl; message = "data\r\n";//data要单独发送一次 send(sockClient, message.c_str(), message.length(), 0); buff[recv(sockClient, buff, 500, 0)] = '\0'; cout<<"data: "<<buff<<endl; ///-----------------------------------------DATA------------------------------------- //要使用Csmtp 发送附件, 需要对Csmtp 头信息进行说明, 改变Content-type 及为每一段正文添加BOUNDARY 名, cout << "-------------------DATA------------------------" << endl; // 头 message = "from:" + user + "\r\nto:" + target + "\r\nsubject:" + title + "\r\n"; message += "MIME-Version: 1.0\r\n"; message += "Content-Type: multipart/mixed;boundary=@boundary@\r\n\r\n"; send(sockClient, message.c_str(), message.length(), 0); // 正文 message = "--@boundary@\r\nContent-Type: text/plain;charset=\"gb2312\"\r\n\r\n" + content + "\r\n\r\n"; send(sockClient, message.c_str(), message.length(), 0); //------------------------------------------------------------------------------------------------ // 发送附件 SendAttachment(sockClient); /*发送结尾信息*/ message = "--@boundary@--\r\n.\r\n"; send(sockClient, message.c_str(), message.length(), 0); buff[recv(sockClient, buff, 500, 0)] = '\0'; cout<<"end_qwertyuiop:"<<buff<<endl; message = "QUIT\r\n"; send(sockClient, message.c_str(), message.length(), 0); buff[recv(sockClient, buff, 500, 0)] = '\0'; cout << "Send mail is finish:" << buff << endl; return 0; }
#include "Csmtp.h" #pragma comment(lib, "Kernel32.lib") int main() { Csmtp mail( 25, "smtp.163.com", "effortscodepanda@163.com",// 来源邮箱 "xxxxx", //密码 "effortscodepanda@163.com" //目标邮箱 ); if (!mail.CReateSocket()) { cout << "ReateSocket failed!" << endl; return -1;// } //标题默认是主机名,内容默认是ip mail.setTitle("test mail"); mail.setContent("this is content. \n yinh"); //附件路径错误,不影响邮件正文的发送。 mail.addfile("test.jpg"); //添加附件 //mail.addfile("test2.png"); //添加附件 mail.SendMail(); //类主函数 system("pause"); return 0; }
这边附件位置是相对位置,因此附件放在工程所在目录,我的test.jpg 是放在 D:\Documents\Visual Studio 2010\Projects\SendEmailTest\SendEmailTest目录的
最终邮件效果:
写代码的小熊猫 ,:) 每天积累一点点,开开心心每一天~